In hot weather, it leaks transmission fluid. Last summer I put in some stop leak (supposedly compatible with Mercon 5) and it did stop the leak. Spring has arrived and it's starting to drip fluid again.

Since it's only leaking a relatively small amount, is it appropriate to gently tighten the pan bolts to specs, or must I go all-out with removing the pan and replacing the gasket?

I don't want to warp anything by tightening the bolts. I do have a diagram of the tightening sequence.

I also understand that I must check to see if it's leaking at the filler tube. I haven't wiped it down and looked at it carefully yet.

Assuming I have to replace the seal, are there any warnings/tips I should be aware of? My procedure would be to drain the fluid (per the manual's instructions), drop the pan and clean it, clean the mating surfaces perfectly, apply sealant, and within 15 minutes of application, reinstall the pan. Tighten bolts to specs. Loosen a bit and re-tighten.

I know this message is disjointed but I'm in an extremely noisy environment at the moment and can't think too clearly with all the distraction.

In hot weather, it leaks transmission fluid. Last summer I put in some stop leak (supposedly compatible with Mercon 5) and it did stop the leak. Spring has arrived and it's starting to drip fluid again.

Since it's only leaking a relatively small amount, is it appropriate to gently tighten the pan bolts to specs, or must I go all-out with removing the pan and replacing the gasket?

I don't want to warp anything by tightening the bolts. I do have a diagram of the tightening sequence.

I also understand that I must check to see if it's leaking at the filler tube. I haven't wiped it down and looked at it carefully yet.

Assuming I have to replace the seal, are there any warnings/tips I should be aware of? My procedure would be to drain the fluid (per the manual's instructions), drop the pan and clean it, clean the mating surfaces perfectly, apply sealant, and within 15 minutes of application, reinstall the pan. Tighten bolts to specs. Loosen a bit and re-tighten.

I know this message is disjointed but I'm in an extremely noisy environment at the moment and can't think too clearly with all the distraction.

Thanks!
Brian

Hello and good day:

Sorry for the the delay in reposens. I would strongly suggest you do a complete Transmission Flush, Replace Transmission Filter, and Pan Gasket.

Your Procedure as out line above sounds correct.

__________________Good Luck and good repairing Sterling_6"You know, just like in that Book, When Jesus beats up Moses to get Religion!!"

I wouldn't add any more fluids to the transmission unless it's the correct Mercon V fluid. You want full synthetic in there, no stop-leak or Lucas stuff. Not that it won't cause problems, but you don't want it to loosen up anything that's stuck in the transmission by throwing in a thick, stop-leak product.

Anyway...to help narrow down the leak, you can add an ounce of UV dye. Then, if you already have a trouble light, buy a UV bulb and after a couple days you'll be able to follow the UV dye to the source of the leak to better diagnose the problem. You may not even have to drop the pan unless you know for a fact that is where the leak is coming from, or you need a service done anyway. If you have over 120K on the vehicle I wouldn't do a transmission flush, as it can do more harm than good (dislodging large particles can clog valve body fluid passages). Not to scare you, as you could still do it, I just advise against it to be safe.

Anyway...to help narrow down the leak, you can add an ounce of UV dye. Then, if you already have a trouble light, buy a UV bulb and after a couple days you'll be able to follow the UV dye to the source of the leak to better diagnose the problem. You may not even have to drop the pan unless you know for a fact that is where the leak is coming from, or you need a service done anyway. If you have over 120K on the vehicle I wouldn't do a transmission flush, as it can do more harm than good (dislodging large particles can clog valve body fluid passages). Not to scare you, as you could still do it, I just advise against it to be safe.

Thanks, guys.

Great idea about the light.

It does seem to be a little risky to so a complete flush with an older transmission as slippage is a real possibility with new fluid. Is dropping the pan, resealing it, and refilling with Mercon 5 equal to a complete flush? In other words, does this put me at risk for slippage with new fluid?

No. Simply changing the fluid in the pan will only remove about 1/3 of the total transmission fluid capacity. The fluid in and around the torque converter can't be removed without a flush. A trans service is OK to do, as replacing 1/3 of the old fluid with fresh fluid shouldn't allow the transmission to excessively slip. If you want you can still do a flush, but as I said, I wouldn't with higher mileage.

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